An accumulator of this generic type is known, for example, from DE 20 2006 001 509 U1. There, a fixing element in the form of a thermoplastically welded tape is used, in order to hold the pole plates of the plate stack together. One major advantage of this arrangement is that the housing of the accumulator can be designed to have thin walls, since it need no longer exert pressure on the plate stack in order to ensure the accumulator is sufficiently resistant to shaking. In order to withstand, in particular extremely severe shaking loads without damage, the housing must, however, still have considerable strength. This leads to the consumption of a large amount of material for the production of the housing, and to the accumulator being heavy. A further disadvantage is that the plate stacks must be manufactured with high geometric accuracy. This is because, on the one hand, the plate stack must be large enough to make contact with the housing all the time, even in the event of a severe shaking load. On the other hand, the plate stack must be sufficiently small that it is not damaged during insertion into the housing. This stringent accuracy requirement for the plate stack and the housing leads to high manufacturing costs.